Google X is testing wind turbine prototypes
Google X is testing huge airborne plane-shaped wind turbines in order to develop renewable energy technologies Google

Google is to start flying giant 84ft-long wind turbine prototypes in April over the skies of California, as part of Project Makani, or rather its work into developing new renewable energy technologies following its acquisition of Makani Power.

Astro Teller, the head of Google X, Google's secretive lab that works on creative, unusual and sometimes crazy ideas (known as "moonshots") told the audience at the South by Southwest (SXSW) festival in Austin, Texas that so far none of the turbines have ever crashed.

"Larry Page said to me, 'make sure you crash at least five of those test versions,'" Teller said, according to the Verge.

"What he meant was... if you're not breaking your experimental equipment, at least some of the time, you could be learning faster. And I know he's right."

So far, the airborne turbines being tested have measured 28ft in length. Each prototype looks like a small plane and comes with eight wind turbines.

The prototypes are tethered to a docking station, but once they are released in windy conditions, the propellers help the contraption to reach an altitude of 1,476 feet.

Once at the right height, the prototypes start making large circles in the sky, which enables each turbine on the contraption to send 600 kW of energy back to Earth.

The turbines are being tested at Pigeon Point in Pescadero, California, which is one of the windiest places in North America, where the speed of the wind can change by up to 20 miles per hours in just a second, while the direction of the wind can change by 90 degrees in a second.

"If this works as designed it would meaningfully speed up the global move to renewable energy," said Teller.

"We didn't want to see [the turbine] crash, but we also feel like we failed somehow. There's magic in everyone believing that we might have failed because we didn't fail."